Testing system



June 3, 1930. w s E, STRQMBERG 1,760,920

TESTING [SYSTEM Filed March so, 1929 2 Sheets-Sheet 1 INVENTOR AT RNEY June 3, 1930. s, STRQMBERG 1,760,920

TESTING SYSTEM Filed March 30, 1929 2 Sheets-Sheet 2 Somme f Tone T O O 20 I o I Bazr (to be Identified L I -:o o o o INVENTOR BY 8. E 5170/0256 A ORNEY Patented June; 1930 11 "1 '7 svnn a. smo enaloe NEW YORKQNV.

'r'nnnennrn-i colvrrimy, A oonron-nrron or NEW;-YO RK 1 Y.; ASSIGNOR ToAMERIoAN TELEPH r 'rns'rnvs SYSTEM V Application area March; 3o, 1 92'a. ser alfu'ol 351,414, M

This inventionlrelates to a} systeml which ,is particularly adapted for testing.

electrical conductors.

' In a testing system such as is usedin connection vwith the installat on and mainte-,

nance of conductors, and especially conduc-j tors in cables andthe like, it iscustomary to i use telephone receiver and condenser'to. make certain tests of the conductors; These;

tests of conductors may consist'of identifying pairs, detecting defective pairs, or numerous telephone receiver to eliminate false signals other well known tests. It is'common practice to connect a condenser 111881168 with the at a central oifice. The telephone receiver and condenser have been heretofore used in separated relation, and for this reason have been found cumbersomeand inconvenient to employ in testing operatlons.

Accordingly, it is one ofthe obj ects of this u invention to provide atestingsystem 01'' the character mentioned above, which is of a simple and compactjnature. v

Another object is to provide a testing system '7 which .is efficientgand comparatively ineXpensive.

These and further objects will be appar--' ent form the I following description, when considered in connection with the accom panying drawing, in which one embodiment of the invention is illustrated.

Referring to the drawing, Figure l is a perspective view of a shell membercarrying a condenser; Fig. 2 is a perspective View of a watch-case receiver with'the shell mem her and associated equipment connected thereto; Fig. 3 is a diagram of the circuit con-I necting the receiver and condenser; and

7 Figs. 4 and 5 are typical circuit diagrams to which the-improved testing system may be applied. F 1

In the drawing the numeral 5'indicates a shell member of cylindrical shape havinga closed end 6. The cylindrical wall ofthe shell member is provided with slots- 7,7 which extend through the rim 8 at the open end of the shell member and are positioned approximately 18.0 degrees apart. cutaway portion 9 is provided between'the slots 7 and extends through said rimJ The por- H RD tion:fl..9 permitsthel connection of electrical conductors jwitha watch-case reseiver to be I presently described; condenser 10 ofjde- V sired capacitance isattached to the end 6,-'and v g lies within v the chamber of the shell member. I'n'the present instance, the condenser" is Shown "P ?P z llustration, as

being. attached to the shell member by means of screws .11. Thesescrews engage lugs eX-.

tending from I the condenser 10,;and are threaded into the closed end 6. However,

other means may be provided for attaching thecondenser'fto the shell member,- orit may:

be-suitablysealed thereto byparafiin or-the I 7 like. [The condenser is preferably enclosed in a casing and insulated therefroinin' the; usual 'mannerifThe condenser 10 1s con-s,

nected to terminals 12 positioned on the end 6 ofthe shell member by conductors which pass in-insulatedrelation through said end.

c The shell. member 5 is adapted to be. clamped on'a Watch-caserec'eiver 13'. This a snug connectiontherewith. "The slots 7 and studsl6 register with eachother when receiver may beef-theordinary type consist ingof an ear-piece and -a'- cylindricalportion extending therefrom. The" cylindrical poro I tion is provided with a pair of studs 16 which. i

project outwardlyjfrom itswalljandlieatl approximately 180 degrees from each other; The shell'memberh fits over the cylindrical portion, and itscircumference is of such dimension that when in position it makes her. The cut-away portionthus providesa clearance .for the conductors, and also eliminates interference by such conductors in the; attachment 'or detachmentflof the shell mem her and receiver.

inforked members i8-as illustrated in Fig.2."

The receiver l3fmaybei aid d v head-band l7'whichmay; terminateat o dwl oog o I I I to "terminals, may be substituted for the lugs,

on the end 6 of the shell member.

the proper conductor-is located the testman" at each end of the line hears atone in his re-- {land 5.

The end of the'lorked members 18 may have pins projecting from their extremities which engage orifices in the stud members 16 to pivotally connect the head-band with the receiver. The stud members 16 thus perform the double function of providing, with the slots 7 otthe shell member, a'bayonet ,joint and also a pivotal mounting for the head-band.

The receiver and condenser are connected 'inseries relation byfa conductor extending Irom the receiver to one of the terminals 12 The condenser and receiver may have a plurality of leads connected herewith. In the present instance, as shown in Figs. 2 and 3, there are threeleadsprovided, tWo of which terminate incontact lugs iii-and 19' and the other ina test P011111" 20.- Glips, of course, or other means by which'the leads may be connected if desired. a The test point 20 is applied to conductor to test the circuit to determine its condition, as Will be explained in conneci-ion-witlrthe examples illustrated in Figs.

To establish a talking circuit in a multiconductorcable, the usual practice is to connect a receiver'across a spare pair of con-' ductors in thecable, and connect a tone between the pair of conductors and groundat one caoleend. At the other cable end the various conductors are tested by a receiver in series With a condenser to ground. Tone heard in the-receiver is an indication that the proper pa r has been found. This testing system can be usedforthis purpose by connecting terminal 19 to ground and applyingthe test point 20 to the various cable con- VVh-at is claimed is:

1. A testing system comprising a watchcase receiver, a shell member shaped to be mounted on the outside of the receiver, a condenser carried by the shell member, and 1 means for attaching the shell member and its associated condenser to the'receiver.

QKA testing system comprising'a Watchcase receiver, a shell member shaped to fit overthe receiver, a condenser carried by the shellmember, and means to secure the receiver and shell member by a bayonet joint connection.

3. A testing system comprising a watchcase receiver, a shell member adapted to fit 7 ductors until the proper conductor is found, 5

as will be more clearly indicated by reference to "Flg. 4; Then the proper conductors are found the tes-tman connects his receiver 13 across the spare pair, using terminals 19' and 19 therebyestablishing a talking circugt1 with a testman at the other endoi the ca e. F

Other conductors in the cable may be then 7 identified, using the connections indicated in F 1 g. 5.- The various cable conductors are tested by means of the test point 20, and when ceiver. 1

Theuse of a condenser of small'capacitance'in 361163 with the test point prevents false signals on Working subscriber lines which by chance may be tested While searching for a desired conductor.

lVhile only two examples of the useof the improved testing system have been illustrated' and'describe'd, it Will be understood that this system is capable of being utilized in othertesting circuits in whicha condenser and recerver are employed, 

